Gripping device for printing presses



March 15, 1960 P. DIETRICH/ETAL 2,928,344

GRIPPING DEVICE FOR PRINTING PRESSES Filed 001;. 7, 195'? thm United States Patent 2,928,344 GRIPPING DEVICE FOR PRINTING vPRESSES Paul Dietrich and Roland Gnther, Augsburg, Germany, assignors to Maschinenfabrik Augsburg-Nurnberg A.G., Augsburg, Germany ApplicationOctober 7,` 1957, Serial No. 688,734 j, Claims priority, application Germany October 25, 1956 9 Claims. (Cl. 101 -412)` This invention relates to a gripping device for printing presses. In particular, the invention is directed to the construction of an adjustable finger of a gripping device which is mounted on a rocking shaft.

To insure a faultless transfer of paper in printing presses, it has been suggested that the grippers can be spring pressed against an eccentric shaft and can be adjusted to the desired paper size by turning the Shaft. This is an expensive construction. It is also known to support the grippers against so-called single adjustable clamp members by means of springs, and to equalize the gripper pressure over the whole width of the paper by turning the single clamp members on a supporting shaft. This adjusting manner is difficult because of the number of grippers, so that under certain conditions an equal pressure on the paper cannot be obtained, and thus transfer difiiculties occur.

These difficulties are avoided by the instant invention in which the gripper device is adjustably mounted on a rocking shaft with the gripper finger being adjustable on the gripper body by means of a threaded bolt which is located in the gripper body. For example, the pressure surface of a spring in the gripper device can be adjusted by means of a threaded bolt, or a threaded bolt with a Wedge-shaped head can be located in the gripper device. The wedge-shaped head of the bolt engages an inclined surface of the gripper finger. The bolt preferably is placed in a recess on the upper side of the gripper body immediately below the gripper finger with the gripper device having a U-shaped cross-section. The pressure spring between the gripper finger and gripper body is psitioned as closely as possible to the front free edge of the gripper finger and within the two side walls of the gripper device so that the spring tension and the wear 0n the axle of the gripper device are kept very small. According to other features of the invention, the gripper devcie can be provided with a slit adjacent the supporting plane of the finger. This slit is approximately perpendicular to the rocking movement direction of the gripper device and can be adjusted by means of threaded bolts. Because of this construction, an exact adjusting and accurate paper transfer is possible with very little expense. Furthermore, the danger of injuring the gripper and interrupting the transfer of paper is avoided because the adjusting bolt and pressure spring are fitted within the gripper device.

The means by which the objects of the invention are obtained are described more fully with reference to the accompanying drawings, in which:

Figure 1 is a cross-sectional view through the gripper device in a printing press;

Figure 2 is a cross-sectional view on the line II-II of Figure l; v

Figure 3 is a top plan view of the gripper device shown in Figure l;

Figure 4 is a cross-sectional view of a modified form of the invention;

Figure S is a cross-sectional view on the line V-V of Figure 4; and

Figure 6 is a cross-sectional view of a further modification.

ln Figure 1, the printing cylinder 1 and the adjacent` l cylinder 2 of a printing press are schematically shown in dash-dot lines.

spect to shaft 5. Each finger 7 has a U-shaped crosssection portion, as shown in Figure 2. A spring 8 is mounted as closely as possible to the front free edge of' the gripper body for urging the finger 7 toward the body 6 by pressing on the bight of the U of finger 7. The distance between the finger 7 and the body 6 can be adjusted in accordance with the necessary conditions by means of a threaded bolt 18 bearing on the pressure surface of spring 8, as shown in Figure l. The top of bolt 18 acts as a stop for limiting the movement of finger 7. This bolt can be turned by means of a wrench inserted in an opening 19 in the finger to obtain a correct adjustment between gripper body 6 and finger 7 and between finger 7 and member 4, respectively. In order to prevent the bolt 18 from being loosened, the extension 20 of body 6 is provided with a longitudinal slit 21, the width of which can be adjusted by means of screw 22. Tightening of screw 22 prevents loosening of bolt 18 during the operation of the gripper device. The U-shaped cross-section of the gripper device permits the spring and adjustment bolt to be located in the gripper body.

As shown in Figures 4 and 5, bolt 9 has a wedge-shaped head 10 in the gripper device. Head 1l) bears on an inclined surface 12 of the gripper finger. Nut 11 on the rear end of bolt 9 can be turned to adjust the distance between finger 7 and body 6. Bolt 9 is mounted in a recess extending perpendicular to the axis of shaft 5 on the upper side of body 6 and immediately below finger 7. Spring 13 urges the bolt toward the front free end 0f finger 7.

In Figure 6, the construction of body 6 and finger 7 and the position of support member 4 is essentially the same as heretofore described. Finger 7 is adjusted by means of bolt 14 which is positioned adjacent the bearing surface 15 for the finger on body 6. By turning this bolt, the width of slit 16 is changed. Slit 16 is approximately perpendicular to the rocking movement o-f the gripper device and is located in the gripper body. Corisequently, the position of bearing surface 15 for finger 7 can be changed to a larger or smaller distance with respect to support member 4. By adjusting bolt 14 for each gripper device, all of the devices can be adjusted to a uniform pressure. Access to bolt 14 is through opening 17 in finger 7, and because of the arrangement and position inside of the gripper body, the bolt is protected against damage and loosening.

Y Having now described the means by which the objects of the invention are obtained, we claim:

1. A gripper device for printing presses, comprising a gripper body adapted to be secured to a rocking shaft, a gripper finger axially aligned with said body and pivotally mounted with respect to said shaft and body, a compression spring carried by said finger and bearing against t dicular to the axis of the rocking shaft, and screwmeans for adjusting the width of said slit.

3. A gripper device as in claim 1, said bolt comprising a serewthreaded bolt having a Vwedge-shaped head engaging an inclined surface on said linger.

'4. A gripper device as in c laim 3, said bolt being mounted beneath said finger and parallel vthere tvo,and a. nut onV said bolt for adjusting the position of the bolt head.

5. A gripper device as in claim 1, said spring being mounted between the side walls of said finger and adjacent the free end of said nger'for urging said body toward said nger.

6. A gripper device as in claim 5, said bodyat thek spring position having a U-shaped cross-section.

7. A gripper device as in claim 5, further comprising a return spring mounted on said bolt for urgingsaid 4 i '1 Vwedge-Shamed head toward the free vend of said nger. 8. A gripper device as in claim l, further comprising Y a slit in said body separating a resilientspring-bearing portion from said body, and said slit extending perpendicular to the axis of the rocking shaft and having its width adjustable by sadbolt;

9. A gripperV device Yas in vclaim 8, further comprising an opening in said finger giving access to said bolt.

References Cited in the file of this patent UNITED STATES PATENTS 

